when i prints struct type variable it prints more byte then it has data type bytes.

[my098]

when I declare
struct student{
int rollno; //it reserve 4 bytes
char name[25]; // it reserve 25 bytes
float marks; // it reserve 4 bytes
// total is 33byte
};

struct student s1; //it reserve 33 bytes
printf("%d",siz eof(s1));
// it prints 36.
// why prints 36 intead 33 because its total bytes is 33..

[weaknessforcats]

Yes, that can happen. When the compiler sees the struct, it tries to align the members on integer boundaries to simplify locating the members in memory.

I this case the int is on an int boundary and you reserve 4 bytes. The array takes 25 bytes so it extends into the next int area by one byte. The compiler then adds 3 pad bytes so the float starts on the next int boundary.